Mobile terminals are freely used while being carried regardless of places. Typical mobile terminals are payment terminals used for credit cards, mobile communication terminals such as mobile phones, and personal digital assistants (PDAs) that are referred to as personal portable terminals. Accordingly, the term “mobile terminal” used herein includes all of these terminals, but the payment terminal will be mainly discussed for convenience of explanation.
A payment terminal stores and processes a large quantity of important data, for example, personal information. Accordingly, it is necessary to use a tamper detection mechanism that may detect hardware or software tamper to hack important data.
Typical tamper is to hack important data by disassemble the payment terminal In other words, a case in which a printed circuit board is arranged is disassembled to hack important data from various circuit parts mounted on the printed circuit board.
Thus, a payment terminal according to a conventional technology includes a case disassembly recognition portion that recognizes disassembly of a case and a hacking blocking portion connected to the case disassembly recognition portion to erase important data when the case is disassembled.
The case disassembly recognition portion is configured in a switching method and recognizes assembly and disassembly of a case. In other words, the case disassembly recognition portion includes a tamper detection pattern provided on a printed circuit board and having two conductive members arranged to be separated from each other and a moving member movably provided between the printed circuit board and the case and electrically connecting the two conductive members by moving therebetween.
The case disassembly recognition portion recognizes assembly of a case as the moving member contacts the conductive member during assembly of a case and disassembly of a case as the moving member is separated from the conductive member during disassembly of a case.
As tamper develops further, a tamper method that disturbs the case disassembly recognition portion has appeared. The developed tamper method uses conductive liquid. After forming a small hole in the case, conductive liquid is injected onto the tamper detection pattern.
When conductive liquid is injected on the tamper detection pattern, the two conductive members separated from each other are electrically connected by the conductive liquid. Accordingly, when the moving member is separated away from the conductive member due to the disassembly of a case, the case disassembly recognition portion may not recognize the disassembly of a case.
Thus, there is a demand for development of a mobile terminal that may deal with the tamper of disturbing the case disassembly recognition portion like the method of injecting conductive liquid onto the tamper detection pattern.